This invention relates to a novel window frame which provides for pressure equalization between window frame and window sash by means of a vent and drain channel extending along the perimeter of the window frame adjacent the sash and to a latch device which provides for opening means for the window while at the same time serving as a sealing device for the said vent and drain channel.
A recent development in window and glass panel doors has resulted in the construction of internal air vents along the sides of the window and door sash in communication with moisture vents at the sides of the sash to communicate exterior air with the interior of the sash and to equalize air pressure with the outside about the periphery of the window and glass panel doors. Such internal vent and drain channels minimize the collection of moisture and tend to equalize the air pressure in a designated channel in the window with the outside air pressure to allow any entrapped moisture or condensation to drain out through the bottom vents. A unique structure of this type is described in U.S. Pat. No. 5,044,121 issued Sep. 3, 1991.
In the case of a horizontally pivotable inside window sash, the present invention provides a mating sash and frame construction incorporating vertical and horizontal vent and drain channels which must be closed off to provide an adequate seal between the outside atmosphere and the inside of the house while, at the same time, allow the air pressure within the vertical and horizontal bottom vent and drain channels in the frame along the outer perimeter of the window sash to equalize with the outside air pressure.
It is therefore an object of this invention to provide a novel window frame with a vent and drain channel and a latching device at each side of the upper end of a horizontally pivotable sash to provide latching and sealing means for the vertical vent and drain channels when the window is closed.
It is an object of another aspect of this invention to provide a latching device for releasing the upper end of a pivotable sash to thereby horizontally pivot the sash on a lower axis.
It is an object of yet another aspect of this invention to provide a latching device for pivoting a sash at its lower end to facilitate the cleaning of the outside surface of the window pane mounted therein.